The Element Boron
Boron is the fifth element in the series of the Periodic Table, and as such an atom of Boron has five protons in its nucleus. This means that a neutral boron atom will attract five electrons, one for each positive proton charge in the nucleus. The innermost electron shell holds two electrons, leaving the Boron atom with three outer shell electrons. The most common isotope of Boron is 11-Boron which has 5 protons and 6 neutrons, though 10-Boron also makes up about 19% of the naturally occurring atoms of this element. This isotope contains 5 protons and 5 neutrons per atom. Under normal circumstances, Boron will lose these three electrons to gain a full outer shell, 1s2. That results in Boron ions that have three more protons than electrons and therefore have a charge of +3. 
<Boron as a Semiconductor Dopant Boron has a number of industrial uses that are not limited to the construction, chemical, agricultural and pharmaceutical sectors. However it is the capacity of Boron to contribute to current flow in solar arrays that is of primary interest. Boron can be made to bond covalently with silicon atoms in a silicon lattice. This addition of a foreign element into an otherwise pure lattice is called doping. How does this work? Doping in the Silicon Lattice We can see from the electron dot diagram of Boron that it possesses three outer shell electrons. When it encounters silicon atoms in a lattice, it is forced to bond covalently with the four silicon atoms surrounding it. 
When we match up the electron pairs in order to have all the elements involved having a full outer shell of electrons, the element Boron causes an empty space where an electron should be. This is also called an Electron Hole, and is fundamental to the operation of the photovoltaic cell. Return from The Element Boron to The Chemistry or return to the Green Planet home page for more Solar Power Facts.
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